


The Colonel's Son

by riggs



Category: Fullmetal Alchemist - All Media Types, Fullmetal Alchemist: Brotherhood & Manga, Harry Potter - J. K. Rowling
Genre: Alternate Universe, Conspiracy, Crossover, Family, Father-Son Relationship, Gen, HP characters exist in Amestris, Harry is Roy's son, Hurt/Comfort, Parental Roy Mustang, Story Retelling, will mostly follow Brotherhood canon
Language: English
Status: In-Progress
Published: 2020-03-10
Updated: 2020-03-10
Packaged: 2021-02-28 00:20:23
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,759
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22904614
Author URL: https://archiveofourown.org/users/riggs/pseuds/riggs
Summary: Roy Mustang is many things. He's a soldier, an alchemist, a loyal friend to some and a deadly enemy to others. But what would happen if he was also a father?Everything is the same, but entirely different.
Relationships: Canon Relationships - Relationship
Comments: 1
Kudos: 28





	The Colonel's Son

**Notes for the Chapter:**

> am I writing this fic, knowing full well that nobody asked for it? fuckin bet  
> but it's been buzzing around in my head for 10 years, so here we go I guess?  
> 

* * *

Eastern Command - 1912

* * *

_Fwip_

The train bombings...

_Krinkle...krinkle......fwip_

Child abductions...

_Fwip........sssst...._

Roy knows the two are connected. He can feel it, like a person standing just behind him. He knows the connection is there, might even hazard a guess as to why, but he just can't see it yet. He needs proof - proof the higher ups aren't willing to wait on. 

Another paper plane glides across the room and falls, just a foot shy of the trash bin, as Second Lieutenant Havoc enters the office.

"Uh...sir? What exactly are you doing?"

"I've been reading my letters of encouragement from Central Command," Roy says dryly as he begins to fold yet another letter. The space from his desk to the bin on the far wall is littered with dejected paper planes.

"Dead end in your investigation then?"

"Stone cold."

The lieutenant kneels to read one of the crumpled letters near his feet. Roy recognizes it. Double bond paper - sturdy, but too heavy to fly far. The message itself is worded politely, but the between-the-lines reeks of condescension. 

His superiors are getting restless. The train bombings haven't yielded any casualties, yet, but the lack of progress in stopping them makes the military look bad. And his search into the abductions of affluent children has come up empty. Regardless, the ransoms have all been paid, and every child accounted for, so it's not a priority to the higher ups.

Every lead Roy's looked into has gone dry, and he's running out of options. 

He tries discussing the matter with Havoc for a while, parsing out his theories and hoping for some angle on the matter that perhaps he's missed. In the end, Havoc is a sympathetic ear, but ultimately no help. 

With nothing new, and his spirits low, Roy folds another plane and sends it flying. The plane is quickly shot down as the office door suddenly swings open. Master Sergeant Fuery appears, gripping the doorknob tight as he exclaims, "Colonel, sir! It's your son! He's been kidnapped!"

A cold chill runs down Roy's spine. Havoc fails to notice and lets out a low laugh. 

"Fuery, I think you've got your wires crossed. The colonel doesn't have any kid-" 

"Where's the ransom note? What does it say?" Roy cuts him off. The smile on Havoc's face slips as he picks up a barely discernible note of panic in the colonel's voice. 

"O-oh, right!" Fuery fumbles with the note in his hands. "It states, _'To the commanding officer of Eastern Command. If you want your son back, you will arrange the payment of 20 million sens. Payment details to follow.'"_

He looks up at the two of them nervously.

"Okay, but if all it says is 'commanding officer' how are we sure it's the colonel's kid?" Havoc asks. "What about the general?"

"We just checked with General Grumman," Fuery insists. "His children and grandchildren are all full grown, and none are reported missing."

Roy sighs and pinches the bridge of his nose. There really is only one possibility then, he thinks bitterly.

He tries to compose himself. Now isn't the time. His subordinates still need their orders. It's ironic that in a moment of such crisis, the pieces finally all slot themselves together in his mind. He knows what he needs to do. 

"Assemble the team, now. I want reports on every warehouse under military use within a mile radius of open train lines, as well as every case file on the recent kidnappings. On the double!"

"Sir!"

Havoc and Fuery are gone, quick to their tasks, and with only a moment alone, a crack appears in his carefully cultivated mask of indifference. A wisp of worry slips through as he falls back into his chair, head in his hands. 

It's going to be okay, he thinks. 

He'll protect his son. 

He has to. 

Because he doesn't know what he'll do if he fails...

* * *

Edward wakes up sitting on a hard, cold stone floor. His shoulders are killing him, probably from sleeping upright for so long, and his mind is still foggy. There are crude shackles on both of his wrists, pulled above his head, keeping him chained to the wall. There are no windows, but small streams of light shine through cracks in the dilapidated metal walls. 

It takes a moment for him to remember how he got there. 

He and Alphonse had been in East City for some re-supply and a short rest. They were walking down a street, nothing out of the ordinary, before they noticed a scuffle in a nearby alley. A boy, couldn't be older than Ed, was being manhandled by two thugs into the back of a truck. He kicked and shouted, giving the thugs a harder time than they probably anticipated, but in the end there was only so much a boy could do against two grown men. 

Ed had thought it would be an easy rescue. He told Alphonse to go find the nearest police before throwing himself into action. Although twice his size, in the end they were no match for a trained alchemist. 

What he hadn't anticipated was the third man, sneaking behind him with a cloth soaked in some sort of chemical that knocks him unconscious. 

That explained the leftover buzzing in his head, then. 

Remembering the boy from before, Ed looks around the room. He's there, but with only a loose shackle around his ankle chaining him to the floor. He's out cold, but breathing evenly, which eases Ed's mind somewhat. 

Soon enough, their captor pays them a visit. The man, Colt, is more unassuming than Ed expected for a child ransomer. He is, however, very eager to share his plan with Ed, once he knows he's in the presence of a state alchemist. Colonel Mustang had recently told Ed about his suspicion that a string of kidnappings were somehow connected to seemingly random terrorist attacks, and Colt is quick to confirm the theory. His organization is using the ransom money from the abductions to fund their efforts to deface the military. And his grand finale is to kill the child of a high ranking official, making it look like the military's fault. 

Edward is the only unforeseen variable, but then, what's one more dead child when they're already this far in? 

The callousness in his voice makes Ed's blood run cold.

He'll give it to this Colt guy, he's smart. He saw Ed fight in the alley, and knew to restrain him with his hands held apart. There isn't much he can do like this, but maybe if the other kid wakes up, they can figure something out. 

Colt leaves eventually, after a few thinly veiled threats to behave, and when the door is shut and the sound of footsteps fades, the kid begins to wake up. 

He's slight, a similar build to Edward, with dark messy hair and brown skin. His bright green eyes are framed with thick, round glasses. 

"Where are we?" is the first thing he asks. He's still blinking a little heavy as he sits up. Whatever Colt drugged them with was strong.

"By the looks of it, an abandoned warehouse," Ed offers. "Probably their base of operations. But 'where specifically' is still up in the air."

The kid nods. "I'm Harry," he says slowly. "Harry Potter. Thank you for helping me back there...even though it only got you pulled into this mess..."

"No worries, it's what I do," Ed grins. "I'm Edward Elric, a state alchemist. And I'm still gonna get us outta here, no doubt about that."

Something like excitement shines in Harry's eyes. "You're the Fullmetal Alchemist!" 

* * *

The office is deathly quiet as Colonel Mustang pours over file after file, rearranging maps and reports with purpose. Behind him, his team is pulling Alphonse Elric up to speed with the day's events. The boy had rushed into Eastern Command yelling that his brother had been kidnapped, and one by one, more puzzle pieces fell into place. 

"I didn't know the colonel had a son," Alphonse says quietly. He's sitting carefully perched on one of the office sofas. Some of Mustang's team are sitting with him, while others stand at the ready. 

Havoc smirks bitterly across from him. "Neither did we, kid. I thought it was a joke at first, but..." He glances to where Mustang is working. Lieutenant Hawkeye brings him another file. He knows he's not meant to see the brief, vulnerable look in the colonel's eyes, or the slight comforting touch of fingers on the desk. They probably aren't entirely aware of it themselves. 

"I just don't get it," Breda muses. "All of the abductions so far have been discreet, almost meticulously planned and never in broad daylight. What's with the sudden boldness? It seems almost amateur."

"It makes sense," Hawkeye says suddenly.

Everyone turned to the center of the room. 

"All of the children so far have been six years old or younger. I image the kidnappers chose their targets because they were easy to dupe and easy to control, but Harry..."

"...is thirteen and neither of those things," Roy finishes. 

"...Not to mention, they took Edward as well. So this time, they've taken two targets who are difficult to control, at an odd time of day. It's completely unlike the kidnappers' prior M.O. It means they're not even trying to be careful. They mean for this kidnapping to be the last."

Mustang gestures to the map on the desk. Everyone gathers around, and Havoc notes the red X's marking military munitions depots. 

"The train bombings were deliberate. They've effectively cut off almost every route for shipping weapons from factories to bases. Meanwhile, the terrorist attacks have also elicited additional emergency orders of weapons. All of those weapons that have been stockpiling only have one route left to take, and they just so happen to be shipping out today." He circles another storage facility. It's relatively close to East City. "This is the only facility left. And along this track lies a large abandoned steel mill...I'll bet anyone here an alchemist's ransom, that's the terrorists' base of operations.

"And it's where we'll find Harry and Edward."

* * *

"Wait, you're Mustang's kid?!"

Harry lets out a small, wry chuckle as he works to break the chain holdings Edward's's wrists. He's drawing small but effective transmutation circles to weaken the metal chains. 

"What, the family resemblance didn't give it away?" Ed laughs awkwardly, not sure how to respond, but Harry just waves it off. "It's fine. Dad always said I look more like my mother."

The chalk he's using breaks, and he curses before fishing in his pockets for another piece.

It makes sense for the son of a state alchemist to be competent with alchemy, but Ed can't help but be impressed. He knows that he and Alphonse are considered geniuses; it's not arrogance, just fact. Most alchemists don't begin their apprenticeships until their late teens, and even then, many spend years just studying alchemic formula. Practical alchemy takes years of study and effort, but here's Harry, a boy Edward's age, doing just that. 

With a flash of light, he pulls the last of the chains apart. Ed gives a small thanks as he's finally able to stand and stretch. 

"I didn't even know the colonel was married..." he thinks aloud.

"He's not," Harry says, sitting on the floor to rest a moment. "He and my mom weren't together when she had me, which is why I have her last name, I guess. But then she died, and I've been living with him ever since."

Edward stops and looks at him. It's not pity in his eyes, but understanding. "I'm sorry to hear that."

Harry flushes, fidgeting like he can't help but look away. "It's okay... I mean, I was only a baby. Not like I remember her anyway..." 

But Ed can tell that he doesn't entirely mean it. He's not one to pry though, so instead he goes to check the only door leading out of the room. Sure enough, it's locked, but with his hands free, that's not much of an obstacle. With a clap, the doors bust open, falling off of their hinges. He turns to Harry with a grin. 

"C'mon, let's get out of this dump."

* * *

The steel mill is crawling with terrorists, but once Mustang's men show up, they make quick work of capturing them all. Edward knew that Alphonse would alert the military of his capture, and so his focus is on finding Colt. 

And if he and Harry cause a little mayhem along the way, no harm done. 

The kid doesn't have the field experience that Edward does, but he's quick to adapt. He's also a wicked fast draw with transmutation circles. It becomes a solid system, with Harry warping metal pathways and subduing enemies from the rear, while Ed does the heavy fighting. 

They reach Colt with little trouble, near the roof. He proves more of a fight than expected, particularly for a man without alchemy, but eventually the two teens manage to knock him out. 

Harry is transmuting a steel rod to restrain him when Mustang finally finds them. Alphonse is hot on his heels, and Ed wastes no time in running to his brother. 

"Ed! Are you ok?" 

"Fine, Al, just a little banged up."

He grins at his little brother, about to fill him in on everything, when the argument next to him suddenly catches his attention. 

"I don't know why you're so upset! We won!"

Mustang looks tired, more stressed than Ed's ever seen him. "You threw yourself into danger. You could've gotten yourself killed-"

"But I didn't," Harry protested. "I helped!"

Mustang grits his teeth. 

Alphonse leans down to whisper in Ed's ear. "He's been so worried this entire time. I knew you'd be okay, brother, but Colonel Mustang hasn't rested since he got the ransom letter for his son..."

Ed can see that, if the bags under the colonel's eyes are any indication. The way Harry talks about him, his dad hung the moon, and the stars to boot, so he knows that they normally have a good relationship. He knows the colonel was probably just scared to lose his son. 

But still...

"He really was a huge help, colonel," Ed speaks up. "I couldn't have gotten out of here without him."

Harry looks to Mustang for some approval, but all he does is sigh. 

"That being the case, Edward, you are still a state alchemist. Harry is a civilian." He looks back to his son. "He needs to remember that." 

Edward _tsks_ in annoyance. "You're being a real hard-ass, you know that?!"

Mustang ignores him. He's quiet for a moment and then says, "Maybe it's for the best I send you to Central..."

Harry's eyes go wide. "Wait, what?"

"In Central...there's a boarding school. Hogwarts Academy. I've been in contact with the Headmaster, discussing your admittance. I was hesitant to send you so far away...but I think now it might be safer for you..."

"You're sending me away." It's not a question. Harry doesn't even sound mad. He just looks shocked. He shrinks in on himself, like he's trying to process what he's just been told. 

To his credit, Mustang doesn't look happy about it either. The pained look on his face is all that's keeping Ed from clocking him. 

"Let's go," he says quietly, and walks away. "We'll talk more at home."

Lieutenant Hawkeye appears and wraps a shock blanket around Harry's shoulders. Edward hadn't even seen her walk up. "Come on," she says gently. "Let's get you home." 

She turns to Ed and Al. "You too, boys."

They ride back into town in a couple of utility vehicles. Hawkeye is driving one, with Mustang sitting shotgun, and Harry and Edward in the back. No one is talking, and he's never felt so awkward in his life.

He can't help the uneasy feeling in his gut. There's no reason for him to get involved. He feels bad for Harry, but he can't fight Mustang on how he wants to raise his son. It sucks, but objectively, Hogwarts is a great school with a top-notch alchemy program. And he can get where the colonel is coming from with his worry - Harry isn't a trained soldier, or a state alchemist. He'd been lucky that Ed was with him.

He scratches at his head and huffs out a sigh. Damn it. Did the colonel have to be such a dick though?!

**Notes for the Chapter:**

> oh, I guess I'm leaving it here? ugh...ending chapters is always so hard
> 
> this first chapter is a very loose retelling of the light novel "The Abducted Alchemist"  
> some dialogue is borrowed from the novel, but I tried to stay away from copy/pasting events as much as possible
> 
> some housekeeping notes:
> 
> \- I'm adhering to Brotherhood canon as much as possible, this is a retelling with some addition and canon divergence, not a true crossover. there won't be any magic, HP characters are alternates born & raised in Amestris
> 
> \- to suit my needs, Roy, Riza, Hughes, and other characters of a similar age have been aged up five years
> 
> \- the Ishvalan War has been pushed back three years  
> this won't affect the story much unless specifically stated, I'm trying to keep careful consideration of the canon timeline
> 
> \- I'm putting Ed's birthday in February, which makes him just a few months older than Harry
> 
> \- also brown Harry is best Harry, y'all can fight me


End file.
